DECODE - Haemodynamic Effects Of Semaglutide and Tirzepatide - a Series of Pilot Studies

What Was Tested

This registered phase 4 trial tested Tirzepatide and Semaglutide.

What is the research question?

It had six arms (groups): Sub-study 1A (experimental), Sub-study 1B (experimental), Sub-study 1C (experimental), Sub-study 2A (experimental) and Sub-study 2B (experimental).

Intra-arterial infusion of semaglutide.

Intra-arterial infusion of Tirzepatide.

Intra-arterial infusion of Saline, Semaglutide and Tirzepatide.

The registry classes the interventions as drug.

More on the Plan

Obesity is also serious, ongoing epidemic.

Hypertension and obesity share a well-known association, but despite extensive research, the mechanisms underlying their association are still poorly understood.

Since one of the most common causes of high blood pressure is overweight or obesity, a healthy diet and weight loss are recommended for patients with stage 1 hypertension (clinic blood pressure ranging from 140/90 mmHg to 159/99 mmHg) before initiating blood pressure-lowering medications.

However, lifestyle interventions, even when successful, result in only moderate weight loss, which is not maintained in the majority of cases.

Who Took Part

Enrollment: 112 planned participants were the target.

It was open to people of any sex aged from 18 years up to 50 years.

Healthy volunteers could join, not only people with the condition.

Examples of who could join: Inclusion Criteria - Participants with normal weight and normal blood pressure. Have given written informed consent to participate. Aged 18 to 50 years (inclusive). Females must be post/peri-menopausal or if of child-bearing potential they are required to use adequate contraception and to have a negative pregnancy test (performed at each visit). Body mass index (BMI) in range 18.5-24.9 kg/m2.

The full record lists 23 inclusion and 23 exclusion criteria; among the exclusions: hypersensitivity to any of the study drugs or excipients; implanted pacemaker or implantable cardioverter defibrillator (icd); known active malignancy.

How the Study Was Run

The set-up was randomized, parallel-group and double-blind.

The participants were allocated by chance, so the Tirzepatide group and the comparison group should start out alike.

Groups ran in parallel: each of the participants stayed in one arm throughout.

Neither the participants nor the staff measuring them knew who was on Tirzepatide, so expectations could not easily colour the readings.

Those kept unaware of assignments: participant and investigator.

It started in 2026-03 with completion listed for 2027-04.

It ran at 1 site in United Kingdom.

Its stated primary purpose is basic science.

What Was Measured

Researchers chose this as the main measure: Sub-study 1A:Change in forearm blood flow parameters after infusion of semaglutide (Ratio) (time frame: 2-2.5 months from screening to follow-up). Sub-study 1A:Change in forearm blood flow parameters after infusion of semaglutide (Absolute flow) (time frame: 2-2.5 months from screening to follow-up). Sub-study 1A: Change in forearm blood flow parameters after infusion of semaglutide (Percentage Change) (time frame: 2-2.5 months from screening to follow-up).

What This Means in Plain Language

Put simply, this is a phase 4, randomized trial of Tirzepatide and Semaglutide in 112 people.

Its status is not yet recruiting; no results are posted to the registry yet, so nothing here describes outcomes.

More context: the Tirzepatide compound page and the Semaglutide compound page, all human trials.